There has been a growing interest in the use of repeater based systems for a variety of radio frequency communications. Advanced repeater systems must coordinate communications between a number of repeaters. The repeaters may be linked together using a variety of inter-repeater communications means. A remote subscriber, such as a mobile radio user, will request a channel to transmit information to other subscribers and other services connected to the repeater system. The repeater system manages the channels and provides a free channel to the calling subscriber.
However, such systems must orchestrate transmissions by each repeater. This is especially important in broadcast situations where a subscriber is communicating to a number of repeaters for rebroadcast to other subscribers in the system. It is inefficient to leave the repeater transmitters on when there is no information to transmit. Therefore, to service each subscriber rapidly, the transmitters should be activated in a reasonably short amount of time to prevent delays in access to the repeater system. Furthermore, it is desirable to activate the transmitters without supplying an additional control line to each repeater. Communications which are conducted over the repeater system must not be misinterpreted for control signals to the transmitters to ensure that the subscribers cannot accidentally disable the transmit control system.
Therefore, there is a need in the art for a transmit control system which provides rapid activation of a number of transmitters. The transmit control system should use efficient control means to provide control to the separate transmitters. The transmit control system also should provide safeguard against accidental activation or deactivation of the transmitters in the system.